HOUSTON, Feb. 5 (Xinhua) -- U.S. crude oil production averaged 13.478 million barrels per day (b/d) during the week ending Jan. 31, up by 238,000 b/d from the previous week, the U.S. Energy Information Administration (EIA) said Wednesday.

The figure rose by 178,000 b/d from the level one year ago, according to the EIA.

More than 80 percent of U.S. crude oil production growth comes from the country's Lower 48 states, which does not include production from Alaska and the Federal Offshore Gulf of Mexico, according to the EIA.

The United States has been a major oil producer in the past years with the help of its shale oil production growth. ■